soon expiring passport and visa inside (Beijing)

Hi ,I will need to renew my passport soon ( will expire in September).I have a working visa inside (also valid till September).Question:when I got new passport, can I still use my old one when traveling abroad, just to show my Chinese visa inside? It will be a lot of troubles for me to apply for new visa , and I might leave China anyway in September. Ideally I want to use my new passport for traveling and old one ( it will be cancelled and returned to me) just to show I have still valid visa when I reenter China, do you know if that is possible? Thanks in advance!